CONCORD -- Two separate crashes caused big backups for the evening commute through Central Contra Costa County on Wednesday evening.

A crash on southbound Highway 680 near Monument Boulevard tied up the Wednesday evening commute after the California Highway Patrol shut down lanes in both directions.

The injury crash occurred just before 6 p.m. when a sedan crashed head-on into a concrete guardrail, the California Highway Patrol said. One person became trapped in the vehicle, but was finally extricated from the vehicle and was believed to have suffered moderate to major injuries. A traffic alert was issued at 6:19 p.m., as officials shut down one northbound lane and three southbound lanes.

About 30 minutes earlier, CHP officers responded to a three-vehicle accident on Kirker Pass Road near Hess Road, in which one of the cars ended up 50 feet down an embankment. One driver was initially found unconscious, but later awoke. No other injuries were reported and it was not immediately clear was caused the accident.

The crash closed several lanes in both directions, causing a significant backup on northbound Kirker Pass.

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